Conventional modern clothes washing machines typically consist of a perforate inner clothes receiving receptacle or basket nested within an outer, wash water retaining tub. An agitator extends into the interior of the basket and is oscillated in order to execute the washing action during the wash and rinse cycles.
Since this washing action is carried out completely within the confines of the basket, the volume of water which is present between the outer tub and the basket does not contribute to the washing or rinsing of the clothes, and this volume of water may be significant in a given washing machine design.
It has heretofore been recognized that water savings could be achieved by causing the water to be circulated from the tub into the basket during the wash and rinse cycles, such that a lower level of water exists in the tub than in the basket.
Examples of such systems are disclosed in U.S. Pat. Nos. 2,869,344 (Bochan); 2,955,448 (Olthuis); and 3,153,924 (Alger). All of these patents are assigned to the assignee of the present application.
During the initial fill cycle, water is introduced both into the basket and the tub, either simultaneously or by flowing through the openings in the basket, such that an equal level tends to exist in both the tub and basket.
Accordingly, at the completion of the fill cycle, the water level in the basket is somewhat below that at which the machine will operate after the recirculation of the water by the recirculation pump achieves a steady state washing or rinsing level in the basket.
This situation tends to produce a difficulty in that most agitators are designed to operate at a given water level and will not operate properly at the initial low water level. That is, there will be high motor torque demands during the beginning of the agitation cycle. Even with start up at the proper washing water level, a significant cost factor in the electric drive motor is the added expense of starting winding in order to accommodate the start up demand torques.
There also can be some fabric damage due to the lowered water level.
A similar situation exists with respect to the spin extraction cycle, which is normally provided in such machines, in which the perforate basket is rotated at high speed in order to extract the wash and rinse water from the clothes.
It is highly desirable for various reasons that the extraction rotation of the basket be not initiated until the water in the tub and basket has been drained through the household plumbing. This need has previously been recognized in the prior art and various arrangements proposed to introduce a delay into the activation of the agitator or basket drive at the beginning of either the wash and rinse or spin cycles, which will enable the pump up of water into the basket in the case of the agitator wash and rinse cycles and the drain down in the case of the spin cycle.
In some of these various approaches, as described in the above-mentioned patents, a delay is introduced electronically in which the controls provide for an interval of pump up or drain down at the initiation of each cycle, prior to activation of the drive clutch. This approach, however, complicates the design and operation of the controls, as well as the clutch components themselves.
In many designs, a relatively simple trouble-free arrangement is provided by a common drive of the recirculation and drain pumps with the same electrical motor driving the pumps, as well as the agitator and/or basket during the machine cycles. While this eliminates the need for separate drive components and/or controls for these elements, the introduction of a delay interval is rendered substantially more complicated.
In U.S. Pat. No. 3,978,956 (Bochan), a mechanical delay is provided for the spin cycle. While the arrangement described in this patent produces a purely mechanical delay in the initiation cycle, it involves a shifting movement of a blocking element which introduces the possibility of a malfunction of the device, preventing actuation of the drive due to hanging up of the blocker part and also variations in the time at which the clutch drive is established to the basket.
Accordingly, it is an object of the present invention to provide a clothes washing machine in which there is introduced a purely mechanical delay to either or both the agitator and/or basket spin drives and which does not require additional controls or operating components associated with the clutch drive.
It is a further object of the present invention to provide a delayed action clutch for such application which operates in a highly reliable manner and which is relatively simple in construction.